1. Field of the Invention
The present invention relates to side impact airbags for vehicles.
2. Background Art
Vehicle airbags are used to protect vehicle occupants in the event of a collision. Airbags were initially provided on the dashboard and steering wheel of vehicles to protect against front end collisions. More recently, side impact airbags have been developed to protect vehicle occupants in the event of a side impact. Side impact airbags are inflated by an inflator that inflates the airbag with a gaseous medium when an impact is detected by side impact sensors provided on the vehicle.
Some prior art side impact airbags when inflated extend from a mounting location on one side of a seat back forwardly between the vehicle door and the occupant to cover the entire side of an occupant's body. This type of side impact airbag, when deployed, extends across the rib cage of an occupant's body. Such airbags may cause additional unwanted rib deflection as they press against rib cage that is generally less robust than a person's hip or shoulder.
Conventional wisdom is that a side impact airbag should be inflated to place a cushion between a vehicle body part intruding into the passenger cabin and a person's body in the event of an impact. However, side impact airbags inflate very rapidly while the intruding structure of the vehicle body is moving toward the vehicle occupant.
One problem with prior art side impact airbags is that the greater the volume of the airbag, the more time is required to deploy the airbag. Larger volume airbags also require larger inflators. Increasing the size of a side impact airbag and its associated inflator also increases the cost of the side impact airbag system. There is a need for a side impact airbag that reduces the time required for full deployment and reduces system cost.
Another problem with side impact airbags is that different areas of the airbag may require different inflation pressure levels and have different size constraints. To address this problem complex baffling arrangements and separate chambering concepts have been proposed. However, complex baffling and separate chambers or separate air bags tend to increase the system cost and may adversely effect deployment performance.
Tests for side impact airbags include the current IIHS high hooded barrier side impact test and a new more severe FMVSS 214 Oblique Pole Test. There is a need to develop side impact airbags that meet all of the requirements of such tests.
There is a need to provide a side impact airbag having a shape that is optimized to manage intruding energy, but not overload the occupant. There is also a need to provide a side impact airbag that loads bio-mechanically appropriate areas of the body. The most appropriate areas for bio-mechanical loading are an occupant's shoulder and pelvis. Bio-mechanical loading of the thorax should be minimized.
The distance between an H point and knee pivot for the 5th percentile female anthropomorphic dummy is less than the distance between the H point and knee pivot of a 50th percentile male anthropomorphic dummy, requiring the female dummy to sit more forward in the seat. As a result, the 5th percentile female anthropomorphic dummy has a pelvis H point that is shifted forward to an extent that is forward of the pelvis H point for the 50th percentile male anthropomorphic dummy. This creates a problem for side airbags designed to cover at least a 50th percentile male occupant because this does not assure forward coverage for 5th percentile females.
Applicants' invention is directed to solving the above problems and fulfilling the above needs as summarized below.